Trailer construction and joint for use therewith

ABSTRACT

A wall for a truck bed and particularly for dump trucks includes planks joined to one another along their lengths and a cap member joined to the upper plank along their lengths. Adjacent planks are joined along respective connecting sides by engagement of a pivot of a first plank within a pivot-receiving slot of a second plank, rotation of the planks with respect to one another about the pivot and attachment by snap-fit engagement. The first plank connecting side includes an arcuate wing and the second plank connecting side includes an arcuate extension, the wing and extension being received respectively in a wing-receiving slot formed in the second plank and an extension-receiving slot formed in the first plank during the relative rotation of the planks. The cap member is joined to the upper plank in a similar manner except that attachment is by welding rather than snap-fit engagement.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to tractor trailers and the construction oftrailer walls thereof. More particularly, the invention relates to thestructural members used to form such a trailer wall. Specifically, theinvention relates to such structural members or planks which areassembled by rotatably engaging one another along their lengths torotate into position and lock into place by a snap fit engagement.

2. Background Information

The construction of trailer walls and the structural elements usedtherein come in a variety of forms. For example, some trailer walls areformed with a plurality of vertical support members with a metal skinattached on the outside thereof. This option provides a smooth exteriorof the truck for reduction of wind resistance during travel and thevertical members additionally provide structures to which tie downmembers such as ropes and chains may be attached to secure loads insidethe trailer. One disadvantage of this configuration is that objects suchas the cargo may create dents from inside the trailer which show on theoutside, thus reducing aesthetic appeal and increasing wind resistance.In addition, there is a tendency for the skin to wear out over time.

An alternate option is the use of vertical planks which may create inessence an interior skin and an exterior skin, or solid planks to createa solid wall. In comparison to horizontal planks, these vertical planksgenerally require more pieces to create a given wall, therebylengthening the assembly period for such a wall. In addition, themultiple joints between the plurality of vertical planks createspotential weak areas which can be more flexible than a single piece ofskin or horizontally elongated planks. Further, vertical joints are lesspreferable for use with trailer walls used on a dump truck, as thevertical joints create wear areas as the material in the truck abradesthe wall at the joints when dumped rearwardly in a direction generallyperpendicular to the vertical joints.

The present invention is concerned with the problems noted above as wellas with providing improved joints between the structural members of atrailer wall.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a wall comprising a first elongatedmember having a connecting side with a pivot and a cantilevered arcuatewing; and a second elongated member having a connecting side forconnecting to the first member connecting side; the second memberconnecting side having a pivot-receiving slot for rotatably receivingthe pivot and an arcuate wing-receiving slot for receiving the wingduring relative rotation of at least one of the first and second memberswith respect to the other.

The present invention also provides a wall comprising a first hollowdouble-walled elongated member having a connecting side with first andsecond projections defining there between an interior space; a secondhollow double-walled elongated member having a connecting side with anarrowed portion including a terminal wall; the first projectionrotatably engaging the second member adjacent the narrowed portionwhereby via rotation of at least one of the first and second memberswith respect to the other member about the first projection, thenarrowed portion is receivable within the interior space; and the twoconnecting sides being adapted to connect to one another to join thefirst and second members together.

The present invention further provides a method of forming a wallcomprising the steps of rotating at least one of a first member and asecond member with respect to the other member whereby a pivot and acantilevered arcuate wing of the first member are respectively receivedby a pivot-receiving slot and an arcuate wing-receiving slot of thesecond member; and connecting the two members rigidly together.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a side elevational view of a truck incorporating the trailerwall of the present invention.

FIG. 2 is a rear elevational view of the truck with portions cut away toshow the trailer wall from the rear end.

FIG. 3 is a perspective view of the plank which is the main structuralmember of the trailer wall.

FIG. 4 is an end elevational view of the plank of FIG. 3.

FIG. 5 is an end elevational view of the cap member of the trailer wall.

FIG. 5A is an end elevational view of a first embodiment of the basemember.

FIG. 6 is a fragmentary end elevational view of two planks prior toengagement during assembly of the trailer wall.

FIG. 6A shows a further stage of assembly and is similar to FIG. 6except that the two planks are engaged and one plank is being rotatedwith respect to the other plank.

FIG. 6B shows a further stage of assembly and is similar to FIG. 6Aexcept showing a further degree of rotation and additional engagementbetween the two planks.

FIG. 6C shows the two planks assembled after complete rotation of thetwo planks with respect to one another and the formation of the snap fitengagement between the two planks.

FIG. 7 is an enlarged sectional view of a portion of the trailer wallindicated in FIG. 2.

FIG. 7A is an enlarged sectional view of the encircled portion of FIG.7.

FIG. 8 is an enlarged sectional view of a portion of the trailer wallindicated in FIG. 2 and includes the first embodiment of the cap member.

FIG. 8A is an enlarged sectional view of the encircled portion of FIG. 8showing the upper joint between the plank and cap member.

FIG. 8B is an enlarged sectional view of the encircled portion of FIG. 8showing the lower joint between the plank and cap member.

FIG. 9 is an enlarged fragmentary sectional view similar to FIG. 7Aexcept showing glue and a seal between the two planks.

FIG. 10 is an enlarged fragmentary sectional view of a portion of thetrailer wall indicated in FIG. 2 and includes the first embodiment ofthe base member.

FIG. 11 is a sectional view similar to FIG. 8 but shows a secondembodiment of the cap member.

FIG. 12 is a fragmentary sectional view showing a second embodiment ofthe base member joined with a plank and attached to the trailer bed.

DETAILED DESCRIPTION OF THE INVENTION

The bed wall of the present invention is indicated generally at as isshown particularly in FIGS. 1-5. Wall 10 is typically used with a cab12, which most preferably has the capability of dumping contents out ofthe bed. Wall 10 includes a plurality of planks 14 and may also includecap member 16 or 130 and a base member 17 or 146. In the preferredembodiment, planks 14 and cap member 16 are elongated and whenassembled, planks 14 are disposed atop one another in lengthwise fashionwith cap member 16 sitting atop the upper plank 14, as seen in FIGS.1-2. Wall 10 may be used with beds which fully enclose a load althoughthe exemplary embodiment is a bed with an open top. Additionally, thebed may be carried on a straight truck as shown in FIG. 1 or as part ofa trailer traditionally pulled by a tractor.

With reference to FIGS. 3-4, plank 14 includes a pair of opposed wallsor sides which are substantially flat and parallel to one another andelongated in the elongated direction of plank 14. These opposed wallsinclude an outer wall 18 and an inner wall 19 which is thicker thanouter wall 18, although walls 18 and 19 may have the same thickness orvary as desired. Preferably, inner wall 19 is disposed along theinterior of the bed to resist denting and to provide additional materialfor a more durable wall. Plank 14 further includes a first connectingside 20 and a second connecting side 22 in opposed relation to firstconnecting side 20. In the figures, first connecting side 20 is shown inan upper position and second connecting side 22 is shown in a lowerposition although plank 14 may be inverted to reverse these relativelocations. Preferably, planks 14 extend in a horizontal direction, butmay also be disposed so that they are elongated in a vertical or otherdirection. First connecting side 20 includes a first edge 24 adjacentouter wall 18 and an opposed second edge 26 adjacent inner wall 19.Second connecting side 22 includes a first edge 28 adjacent outer wall18 and an opposed second edge 30 adjacent inner wall 19 which are thusin positions corresponding to first edge 24 and second edge 26 of firstconnecting side 20. Plank 14 also includes a series of strengtheningribs 32 extending between walls 18 and 19 and being perpendicularthereto. Plank 14 defines a plurality of hollow chambers 33 which aregenerally bound by outer wall 18, inner wall 19 and strengthening ribs32. One of hollow interiors 33 is bounded on one end by the structureforming a narrowed portion 54 of plank 14 along first connecting side20, narrowed portion 54 being further defined below.

In accordance with one of the main features of the invention and withcontinued reference to FIGS. 3-4, the structure of one of the joints ofplank 14 is described. Plank 14 defines a pivot-receiving slot oropening 34 adjacent first edge 24 of first connecting side 20. Plank 14further includes an arcuate extension 36 which separates pivot-receivingslot 34 from an arcuate wing-receiving slot 38. Slot 38 is bounded onthe outer part of its curvature by an arcuate wall 40 so that extension36 and wall 40 define slot 38 therebetween. Extension 36, slot 38 andwall 40 are disposed adjacent first edge 24 of first connecting side 20.Plank 14 further includes an engaging member in the form of a taperedwall 42 which tapers inwardly from inner wall 19 adjacent second edge 26of first connecting side 20. Tapered wall 42 defines a slot 44 boundedon one side by a ledge 46 and elongated in the elongated direction ofplank 14. Plank 14 further includes a terminal wall 48 along firstconnecting side 20 which extends perpendicular to sides 18. Terminalwall 48 defines a shallow channel 50 bounded on either side by a pair ofshort projections 52. The structure along first connecting side 20constitutes narrowed portion 54 of plank 14.

In accordance with one of the main features of the invention and withcontinued reference to FIGS. 3-4, the structure of the other joint ofplank 14 is described. Along second connecting side 22, plank 14includes a first projection 56 adjacent first edge 28 and a secondprojection or engaging member 58 along second edge 30 whereby firstprojection 56 and second projection 58 are in opposed relation to oneanother and substantially aligned with respective walls 18 and 19. Firstprojection 56 terminates in a pivot 60 which is rounded and extendsinwardly toward second edge 30. An arcuate wing 62 extends inwardly fromfirst projection 56 toward second edge 30 and is spaced from pivot 60whereby plank 14 defines an arcuate extension-receiving slot 64 betweenpivot 60 and wing 62. First projection 56 and second projection 58define an interior space 66 therebetween. Plank 14 defines a relativelyshallow slot 67 at the base of second projection 58 opposite interiorspace 66. Second projection 58 also includes an inwardly extending ledge68.

With reference to FIG. 5, cap member 16 is described. Cap member 16includes an inverted U-shaped portion 70 having an outer wall 72 and anopposed inner wall 73 extending downwardly from an intervening cap wall74 which is thicker than walls 72 and 73. Extending downwardly from alower end 76 of inner wall 73 is an extension wall 78 which tapersdownwardly and inwardly from lower end 76. Together, extension wall 78and inner wall 73 form an interior wall 80. Extension wall 78 terminatesin a tip 82 which angles inwardly from interior wall 80 in a directiongenerally towards outer wall 72. Outer wall 72 terminates in a structurewhich is similar to the structure of plank 14 adjacent first edge 28 ofsecond connecting side 22. More specifically, wall 72 terminates in apivot 84 which is rounded and extends inwardly toward inner wall 73. Anarcuate wing 86 extends inwardly and downwardly from outer wall 72 andis spaced from pivot 84 whereby wing 86 and pivot 84 define an arcuateextension-receiving slot 88 therebetween. Spaced upwardly from wing 86and extending inwardly from wall 72 is a knob or projection 90 having alower ledge 92 whereby a space 94 is defined between ledge 92 and wing86.

With reference to FIG. 5A, base member 17 is very similar to plank 14except that the bottom end thereof is squared off. As such, base member17 includes an outer wall 110 and an inner wall 112 in opposed relationto one another, each of which are substantially flat and parallel to oneanother and elongated in the elongated direction of base member 17. Likeplank 14, inner wall 112 is thicker than outer wall 110, although thewall thicknesses may be varied as desired. The thicker inside wall isused for the same purpose as related to plank 14 and also provides abetter structure for welding to the trailer bed as later discussed.Because base member 17 is squared off on the bottom, it includes onlyone connecting side 114 which is the same as first connecting side 20 ofplank 14 and is numbered in the same manner. Thus, the main distinctionbetween plank 14 and base member 17 is a bottom wall 116 which issubstantially flat and perpendicular to walls 110 and 112.

In accordance with one of the main features of the invention and withreference to FIGS. 6-6C, the assembly of wall 10 is described. FIG. 6shows two planks 14 prior to engagement with one of the planks moving inthe direction of Arrow A toward the other plank to initiate the assemblyprocess. FIG. 6 additionally shows that the second connecting side 22 ofone plank 14 is approaching the first connecting side 20 of the otherplank 14 and in particular, pivot 60 of the one plank 14 is movingtoward the pivot-receiving slot 34 of the other plank 14. FIG. 6 alsoshows that sides 18 of one plank 14 are substantially perpendicular toside 18 of the other plank 14. However, the plank 14 which is moving inthe direction of Arrow A need not be disposed perpendicularly asdescribed. For instance, that plank 14 may be angled so that wing 62 isdisposed somewhat below pivot 60 as it approaches the other plank 14,among other suitable initial positions.

FIG. 6A shows the two planks 14 engaged with one another. In particular,pivot 60 has been received within pivot-receiving slot 34, wing 62 hasbeen received within wing-receiving slot 38 and extension 36 has beenreceived within extension-receiving slot 64. This engagement hasoccurred by moving the two planks toward one another (as shown in FIG.6) and rotating one of the planks in the direction of Arrow B in FIG. 6Aabout an axis 96 (FIGS. 3 and 6A) which extends in the elongateddirection of the planks 14. More particularly, rotation in the directionof Arrow B has caused wing 62 to enter part way into wing-receiving slot38 and extension 36 to enter part way into extension-receiving slot 64.Rotation in the direction of Arrow B has also moved the secondprojection 58 of the one plank 14 toward second edge 26 of firstconnecting side 20 of the other plank 14.

FIG. 6B shows the two planks in a further stage of assembly, havingrotated an additional amount in the direction of Arrow C whereby secondprojection 58 is in contact with tapered wall 42 of the other plank 14.In addition, FIG. 6B shows second projection 58 moving away from taperedwall 42 in the direction indicated by Arrow D as rotational force in thedirection of Arrow C is further applied, thereby allowing secondprojection 58 to slide along the outer surface of tapered wall 42. Slot67 facilitates the bending of projection 58 to aid in the movement ofprojection 58 in the direction of Arrow D.

FIG. 6C shows the two planks 14 in a joined position, whereby ledges 46and 68 of the respective planks are engaged in a snap fit engagement. Inthis joined position, projections 52 of the other plank 14 abuts or isclosely adjacent to the strengthening rib 32 adjacent second connectingside 22 of the one plank 14. Channel 50 of the other plank is thusadditionally bounded by said rib 32 of the one plank 14. FIG. 6C alsoshows sides 18 and 19 of each plank aligned with respective sides 18 and19 of the other plank 14, thus forming parallel and substantially flatwalls on the interior and exterior. During assembly, narrowed portion 54of the other plank 14 is received within interior space 66 of the oneplank 14 to facilitate the formation of the substantially flat interiorand exterior walls of wall 10.

It is noted that even without the snap fit engagement between ledges 46and 68 of respective planks 14, in a position analogous to that of FIG.6C, the two joined planks 14 may not move in a linear fashion along anyline perpendicular to axis 96. The engagement provided by pivot 60, wing62 and extension 36 through rotational engagement of the two planks 14creates a joint preventing such linear movement. The only possiblelinear movement of the two joined planks 14 with respect to one anotheris along axis 96. Such movement is more a theoretical matter than apractical one, however, as a tremendous force would be required toovercome the frictional engagement between the two joined planks 14 toprovide such movement.

Cap member 16 is joined to a plank 14 along first connecting side 20thereof in a very similar manner as described with reference to thejoining of two planks 14 and as shown in FIGS. 6-6C. To join cap member16 to plank 14, the same procedure shown in FIGS. 6 and 6A is followedexcept that cap member 16 takes the place of the one plank 14 whichmoves in the direction of Arrow A in FIG. 6 and rotates in the directionof Arrow B in FIG. 6A. Cap member 16 then rotates in a manner similar tothat shown in FIG. 6B with respect to plank 14 and ends up in a joinedposition analogous to FIG. 6C. However, cap member 16 does not include amember analogous to second projection 58 which engages tapered wall 42of the other plank 14 and provides a snap fit engagement betweenrespective ledges 46 and 68. Instead, tip 82 of interior wall 80 comesto rest on inner wall 19 of the plank 14 to which cap member 16 isjoined. The joined position of cap member 16 and plank 14 is shown inFIG. 8 with enlargements of the joining areas shown in FIGS. 8A and 8B.With reference to FIG. 8A, the final engagement between plank 14 and capmember 16 adjacent first connecting side 20 of plank 14 differs from theplank-to-plank joint in that only one of projections 52 engages capmember 16. In particular, this one projection 52 engages ledge 92 of capmember 16. With reference to FIG. 8B, cap member 16 is joined to side 19by a weld 98.

Where a bed is used for hauling a slurry or any material havingsufficient liquid to cause a leakage problem, it may be desired to havewalls which are sealed to the flow of liquid. With reference to FIG. 9,the present invention provides such an option. Specifically, glue orseals may be used between adjoining planks 14. FIG. 9 shows glue 100 atfour different locations, that is locations where two adjoining planks14 are in contact or are closely adjacent one another. Specifically, oneof the glue locations is between the rotationally engaging structure.Another glue location is adjacent the snap fit engagement. Additionally,glue may be used between projections 52 and the adjacent strengtheningrib 32 of an adjoining plank 14. Glue may also be inserted in the otherinterior spaces defined between the two planks 14, such as channel 50.Another option is to use a seal 102 typically of a polymeric material.Seal 102 is shown disposed in channel 50, although another seal may beused in an interior space 104 between planks 14.

With reference to FIG. 10, the connection between base member 17 and atrailer bed 118 is described. Trailer bed 118 includes an upper wall120, a lower wall 122 in opposed relation to wall 120 and a side wall124 extending between walls 120 and 122. Base member 17 is connected totrailer bed 118 with inner wall 112 of base member 17 flat against sidewall 124 of trailer bed 118. Welds shown at 126 and 128 secure basemember 17 to trailer bed 118. As is evident, base member 17 could bereplaced by plank 14 whereby second connecting side 22 of plank 14 wouldbe exposed and might project below lower wall 122, but otherwise therewould no real distinction between using plank 114 in place of basemember 17.

With reference to FIG. 11, cap member 130 is described. Cap member 130is similar to cap member 16 except extension wall 78 which tapers fromthe U-shaped portion of cap member 16 is replaced by an L-shaped portionwhereby cap member 130 is generally rectangular in cross-section exceptfor a portion which is filled by a portion of a plank 14 when cap member130 is attached to said plank 14. More particularly, cap member 130includes an inverted U-shaped portion 132 having an outer wall 134 andan opposed inner wall 136, each extending downwardly from an interveningcap wall 138. Inner wall 136 is longer than outer wall 134. Cap member13 includes a connecting wall 140 which extends perpendicularly from alower end 142 of inner wall 136 and generally toward outer wall 134.Connecting wall 140 has a terminal end 144. Cap member 130 is connectedto an upper plank 14 in the same manner as is cap member 16 except thatinstead of welding tip 82 of cap member 16 to inner wall 19 of plank 14,connecting wall 140 of cap member 130 is welded at weld 145 to side wall19 of plank 14 adjacent terminal end 144 of connecting wall 140. Outerwall 134 terminates in a structure which is the same as the structure atthe terminal end of outer wall 72 of cap member 16 and the terminalstructure is numbered in the same manner as that of cap member 16.

With reference to FIG. 12, base member 146 is described, which is asecond embodiment of a base member for use with wall 10. Whereas basemember 17 is configured to attach to trailer bed 118 so that wall 10extends upwardly alongside trailer bed 118, base member 146 isconfigured so that wall 10 sits atop trailer bed 118. Base member 146 isa generally U-shaped member having a first leg 148 and a second leg 150spaced from leg 148, each leg extending from an intervening base 152 anddefining an interior space 154 therebetween. Base member 146 furtherincludes an arcuate stabilizing arm or support 156 extending from secondleg 150 away from interior space 154. A connecting portion 158 of secondleg 150 is disposed between stabilizing arm 156 and base 152. Adjacentthe intersection of connecting portion 158 and base 152, a first rib 160extends from connecting portion 158 away from interior space 154 and asecond rib 162 extends from base 152 away from interior space 154. Firstrib 160 and second rib 162 define a concave rest 164 therebetween.

When assembled, a plank 14 sits atop connecting portion 158 of secondleg 150 of base member 146. Pivot 60 of second connecting side 22 ofplank 14 is seated within concave rest 164 and second projection 58 isseated on connecting portion 158 and spaced inwardly from base 152.Inner wall 19 of plank 14 rests against the upper portion of arcuatestabilizing arm 156 and is connected thereto by a weld 166. Plank 14 isalso connected to base member 146 by a weld 168 along second rib 162 andpivot 60.

With continued reference to FIG. 12, base member 146 is connected totrailer bed 118 as follows. Side wall 124 of trailer bed 118 is receivedwithin interior space 154 of base member 146 whereby side wall 124 andbase 152 are closely adjacent or abut one another. Second leg 150 ofbase member 146 sits atop upper wall 120 of trailer bed 118. First leg148 of base member 146 is disposed below lower wall 122 of trailer bed118 and is attached thereto by a weld 170. A flat floor liner 172 liesatop upper wall 120 of trailer bed 118 and is positioned so thatrespective edges of liner 172 and second leg 150 of base member 146 abutone another to form a flat floor surface disposed above upper wall 120.Base member 146 is attached to liner 172 along the above-rated abuttingedges by a weld 174. Liner 172 may be eliminated if desired in whichcase second leg 150 would be attached directly to upper wall 120 oftrailer bed 118.

Thus, wall 10 provides a rigid joint between adjacent planks 14 andbetween a plank 14 and a cap member 16 to provide a sturdy wall having aflat exterior surface to minimize wind resistance during travel and aflat interior surface formed by respective interior walls 18 which arerelatively thick to provide durability. In addition, in the preferredembodiment, planks 14 are elongated in a horizontal direction such thatthe joints between the planks are generally aligned with the directionof the material being dumped out of the rear of the bed, to preventundue wear from joints which are transverse to that flow, as discussedin the background of the present application. In addition, while wall 10may be formed of solid members having the same joints described herein,wall 10 is a generally hollow member which provides a relativelylightweight wall which is simultaneously strong and durable. As with thejoinder of cap member 16 or 130 with a plank 14, the joinder between twoplanks 14 could use a weld to tie them together as opposed to a snap fitengagement described herein. However, the snap fit engagement provides asimple, economical and sure means of securing the planks together andeliminates the need for welding the two planks together, which can be atime-consuming process. Other fasteners such as screws or rivets may beused to join adjacent planks together or a plank to a cap member,although again this is a time-consuming process and in addition is lesspreferable in use with relatively thin walls 18 and 19 of planks 14. Inaddition, rivets, bolts or screws would be at odds with creating a flatinterior wall, since such fasteners would either present a projectioninto the interior of the bed or need to be countersunk, which wouldweaken wall 10.

Wall 10 also provides a secure connection to the trailer bed of a truckwhether attached to the side of a trailer bed or atop the trailer bed.Wall 10 includes a novel base member configured to receive one of planks14 whereby plank 14 is securely seated atop the base member and the basemember is securely attached to the trailer bed.

Each member forming wall 10 is preferably formed of metal although othersuitable materials may be used depending on the use of the wall. Forinstance, plastic may be used for certain applications. While metal ispreferred for use with a wall, the invention is not limited to theformation of walls and has applicability to the formation of wallsgenerally.

A variety of alterations to the exemplary embodiment may be made withoutdeparting from the spirit of the invention. For example, wing 62 andwing-receiving slot 38 could be eliminated whereby only pivot 60 of oneplank 14 would rotationally engage the other plank 14 withinpivot-receiving slot 34. Due to the inward extension of pivot 60, oncethe two planks 14 have been joined, pivot 60 engages extension 36 or mayengage an analogous structure in order to prevent separation of the twoplanks 14 adjacent first edge 24 of one plank and first edge 28 of theother plank. In addition, cap member 16 could be connected to a plank 14with a snap fit engagement. However, in order to provide a cap member 16which is wider than planks 14 and to simultaneously provide superiorsupport against inward rotation of cap member 16, it would be necessaryto include additional structure to provide a snap fit engagement,whereby such structure would be along inner wall 19. While this isfeasible, it is preferable to provide a plurality of planks 14 which aresubstantially identical and thus interchangeable, which expeditesassembly and eliminates the production and related costs of an alteredplank similar to plank 14.

In the foregoing description, certain terms have been used for brevity,clearness, and understanding. No unnecessary limitations are to beimplied therefrom beyond the requirement of the prior art because suchterms are used for descriptive purposes and are intended to be broadlyconstrued.

Moreover, the description and illustration of the invention is anexample and the invention is not limited to the exact details shown ordescribed.

1. A wall comprising: a first elongated member having a connecting side with a pivot and a arcuate wing; and a second elongated member having a connecting side for connecting to the first member connecting side; the second member connecting side having a pivot-receiving slot for rotatably receiving the pivot and an arcuate wing-receiving slot for receiving the wing during relative rotation of at least one of the first and second members with respect to the other.
 2. The wall of claim 1 wherein the pivot-receiving slot and the wing-receiving slot are separated by an arcuate extension; and wherein the pivot and the arcuate wing define there between an arcuate extension-receiving slot for receiving the extension during the relative rotation.
 3. The wall of claim 2 wherein the first and second members are joined together by a snap-fit engagement.
 4. The wall of claim 3 wherein the first member connecting side has first and second opposed edges; wherein the pivot and wing are adjacent the first edge; wherein a projection is adjacent the second edge; wherein the second member connecting side has first and second opposed edges; wherein the extension, pivot-receiving slot and the wing-receiving slot are each adjacent the first edge of the second member connecting side; and wherein the projection adjacent the second edge of the first member forms a snap-fit engagement with the second member adjacent the second edge of the second member connecting side when the first and second members are joined together.
 5. The wall of claim 1 wherein the first member connecting side includes a projection spaced from the wing whereby the projection and the wing define an interior space there between; and wherein the second member connecting side includes a narrowed portion receivable within the interior space.
 6. The wall of claim 5 wherein the first member connecting side has first and second edges; and wherein the pivot and wing are adjacent the first edge of the first member connecting side and the projection is adjacent the second edge thereof.
 7. The wall of claim 6 wherein the second member connecting side has first and second edges; wherein the pivot-receiving slot and arcuate wing-receiving slot are adjacent the first edge; and wherein the narrowed portion includes a tapered wall adjacent the second edge of the second member connecting side.
 8. The wall of claim 7 wherein the tapered wall includes an outwardly extending ledge and the projection includes an inwardly extending ledge adapted to connect to the ledge of the tapered wall in a snap-fit engagement.
 9. The wall of claim 5 wherein the narrowed portion bounds a hollow interior of the second member.
 10. The wall of claim 9 wherein each of the first and second members have a pair of spaced walls each extending from the respective connecting sides; and wherein each of the members is substantially hollow.
 11. The wall of claim 10 wherein the second member includes a strengthening rib extending between and connected to each of the spaced walls; and wherein the strengthening rib, the narrowed portion and the spaced walls define the hollow interior of the second member.
 12. The wall of claim 5 wherein each of the members is substantially hollow; wherein a pair of spaced walls extends respectively from the connecting side of each member; wherein a strengthening rib connects the spaced walls of the first member adjacent the connecting side thereof; wherein the narrowed portion includes a terminal wall which bounds a hollow interior of the second member and which is disposed adjacent the strengthening rib when the members are connected together.
 13. The wall of claim 12 wherein a pair of spaced projections extend outwardly from the terminal wall and define there between a channel which faces the strengthening rib.
 14. The wall of claim 13 wherein the spaced projections abut the strengthening rib when the two members are joined.
 15. A wall comprising: a first hollow double-walled elongated member having a connecting side with first and second projections defining there between an interior space; a second hollow double-walled elongated member having a connecting side with a narrowed portion including a terminal wall; the first projection rotatably engaging the second member adjacent the narrowed portion whereby via rotation of at least one of the first and second members with respect to the other member about the first projection, the narrowed portion is receivable within the interior space; and the two connecting sides being adapted to connect to one another to join the first and second members together.
 16. The wall of claim 15 wherein the second projection and the narrowed portion are connected together by a snap fit engagement.
 17. The wall of claim 15 wherein the first projection terminates in a pivot.
 18. The wall of claim 17 wherein the connecting side of the second member includes a cantilevered arcuate extension defining a pivot-receiving slot for receiving the pivot during the rotation.
 19. The wall of claim 18 wherein the first projection includes a cantilevered arcuate wing; wherein the wing and the pivot define there between an arcuate extension-receiving slot for receiving the extension during the rotation.
 20. The wall of claim 19 wherein the connecting side of the second member includes an arcuate wing-receiving slot for receiving the wing during the rotation.
 21. A method of forming a wall comprising the steps of: rotating at least one of a first member and a second member with respect to the other member whereby a pivot and a cantilevered arcuate wing of the first member are respectively received by a pivot-receiving slot and an arcuate wing-receiving slot of the second member; connecting the two members rigidly together.
 22. The method of claim 21 wherein the connecting step includes forming a snap fit engagement between the two members to provide the rigid connection.
 23. The method of claim 21 wherein the first and second members are generally hollow; wherein the rotating step includes receiving a narrowed portion of the second member within an interior space defined between the wing and a projection of the first member; the narrowed portion including a terminal wall. 